The description on the package says (note: typos are in original text):

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Who will carefully consult the Chords Trainer, will put himself in a condition to apply, with an own harmonical instrument, not only the chords, but also the relative harmonical successions.

Obesity is a common disorder with many complications. Although chronodisruption plays a role in obesity, few epidemiological studies have investigated the association between artificial light at night (ALAN) and obesity. Since sleep health is related to both obesity and ALAN, we investigated the association between outdoor ALAN and obesity after adjusting for sleep health. We also investigated the association between outdoor ALAN and sleep health. This cross-sectional survey included 8526 adults, 39–70 years of age, who participated in the Korean Genome and Epidemiology Study. Outdoor ALAN data were obtained from satellite images provided by the US Defense Meteorological Satellite Program. We obtained individual data regarding outdoor ALAN; body mass index; depression; and sleep health including sleep duration, mid-sleep time, and insomnia; and other demographic data including age, sex, educational level, type of residential building, monthly household income, alcohol consumption, smoking status and consumption of caffeine or alcohol before sleep. A logistic regression model was used to investigate the association between outdoor ALAN and obesity. The prevalence of obesity differed significantly according to sex (women 47% versus men 39%, p < 0.001) and outdoor ALAN (high 55% versus low 40%, p < 0.001). Univariate logistic regression analysis revealed a significant association between high outdoor ALAN and obesity (odds ratio [OR] 1.24, 95% confidence interval [CI] 1.14–1.35, p < 0.001). Furthermore, multivariate logistic regression analyses showed that high outdoor ALAN was significantly associated with obesity after adjusting for age and sex (OR 1.25, 95% CI 1.14–1.37, p < 0.001) and even after controlling for various other confounding factors including age, sex, educational level, type of residential building, monthly household income, alcohol consumption, smoking, consumption of caffeine or alcohol before sleep, delayed sleep pattern, short sleep duration and habitual snoring (OR 1.20, 95% CI 1.06–1.36, p = 0.003). The findings of our study provide epidemiological evidence that outdoor ALAN is significantly related to obesity.

* Department of Zoology, The University of Melbourne, 3010 VIC, Australia

The mechanisms underpinning the ecological impacts of the presence of artificial night lighting remain elusive. One suspected underlying cause is that the presence of light at night (LAN) supresses nocturnal production of melatonin, a key driver of biological rhythm and a potent antioxidant with a proposed role in immune function. Here, we briefly review the evidence for melatonin as the link between LAN and changes in behaviour and physiology. We then present preliminary data supporting the potential for melatonin to act as a recovery agent mitigating the negative effects of LAN in an invertebrate. Adult crickets (Teleogryllus commodus), exposed to constant illumination, were provided with dietary melatonin (concentrations: 0, 10 or 100 µg ml−1) in their drinking water. We then compared survival, lifetime fecundity and, over a 4-week period, immune function (haemocyte concentration, lysozyme-like and phenoloxidase (PO) activity). Melatonin supplementation was able only partially to mitigate the detrimental effects of LAN: it did not improve survival or fecundity or PO activity, but it had a largely dose-dependent positive effect on haemocyte concentration and lysozyme-like activity. We discuss the implications of these relationships, as well as the usefulness of invertebrates as model species for future studies that explore the effects of LAN

It is well established that artificial night lighting can influence animal orientation, but there is less information about its effects on other behaviors. Previous work suggested that light pollution can affect both seasonal and daily patterns of behavior. The aim of our study was to investigate the effects of artificial night lighting and daytime traffic noise on the timing of dawn and dusk singing in 6 common songbirds. We recorded singing behavior in 11 nonurban plots: 2 plots with light, but no noise, 3 with light and noise pollution, 3 with noise, but no light, and 3 undisturbed forests. Our results show that artificial night lighting, but not noise, leads to an earlier start of dawn singing in 5 out of 6 species, ranging on average from 10min for the song thrush to 20min for the robin and the great tit. This effect was strongest at higher light intensities. We further show that dusk song is also affected: 3 species continued dusk singing for longer in lighted areas, but the effect was smaller than that observed for dawn song (from about 8min for the blackbird to 14min for the great tit). For all species, onset and cessation of singing changed relative to sunrise and sunset with the progress of the season. Rain delayed the onset of singing at dawn and advanced the cessation at dusk. We discuss the implications of our findings in the context of sexual selection.

Urbanization has been identified as a global threat to biodiversity. Human population growth in coastal areas, including estuaries, is expected to increase considerably in coming decades, which will result in a proliferation of infrastructure such as jetties, wharfs and marinas. This infrastructure is often associated with artificial night lighting, yet the implications of these unnatural lighting regimes for the fish fauna in coastal ecosystems are unknown.
We conducted novel, night-time surveys of the fish community directly adjacent to an artificial structure using an acoustic camera (didson). By manipulating the artificial lighting conditions (lighting either ‘on’ or ‘off’), we tested the effects of artificial light on fish abundance and behaviour.
Clear differences in the abundance of fish were observed between the two light treatments. The occurrence of large-bodied predators (>500 mm TL) increased when the artificial lights were on. The behaviour of these fish also differed as they attempted to maintain their position within the illuminated area adjacent to the associated anthropogenic structure. The abundance of small shoaling fish also increased when the lights were on.
It is possible that the conditions created by artificial lighting benefit piscivores through the concentration of prey and enhanced foraging capabilities in the case of visual predators. This has the potential to create unnatural top–down regulation of fish populations within urban estuarine and coastal waters.
Synthesis and applications. As a consequence of a positive phototaxic response, the findings of this study suggest that artificial light often associated with man-made structures has the potential to alter fish communities within urban estuarine ecosystems by creating optimal conditions for predators. Future coastal developments should consider the ecological implications of lighting on aquatic communities. We recommend that lighting be minimized around coastal infrastructure and the use of red lights, which have limited penetration though water, be considered.

Increasing evidence points to associations between light-dark exposure patterns, feeding behavior, and metabolism. This study aimed to determine the acute effects of 3 hours of morning versus evening blue-enriched light exposure compared to dim light on hunger, metabolic function, and physiological arousal. Nineteen healthy adults completed this 4-day inpatient protocol under dim light conditions (<20lux). Participants were randomized to 3 hours of blue-enriched light exposure on Day 3 starting either 0.5 hours after wake (n = 9; morning group) or 10.5 hours after wake (n = 10; evening group). All participants remained in dim light on Day 2 to serve as their baseline. Subjective hunger and sleepiness scales were collected hourly. Blood was sampled at 30-minute intervals for 4 hours in association with the light exposure period for glucose, insulin, cortisol, leptin, and ghrelin. Homeostatic model assessment of insulin resistance (HOMA-IR) and area under the curve (AUC) for insulin, glucose, HOMA-IR and cortisol were calculated. Comparisons relative to baseline were done using t-tests and repeated measures ANOVAs. In both the morning and evening groups, insulin total area, HOMA-IR, and HOMA-IR AUC were increased and subjective sleepiness was reduced with blue-enriched light compared to dim light. The evening group, but not the morning group, had significantly higher glucose peak value during blue-enriched light exposure compared to dim light. There were no other significant differences between the morning or the evening groups in response to blue-enriched light exposure. Blue-enriched light exposure acutely alters glucose metabolism and sleepiness, however the mechanisms behind this relationship and its impacts on hunger and appetite regulation remain unclear. These results provide further support for a role of environmental light exposure in the regulation of metabolism.
Fished from the ALAN Research Literature Database

We investigated sleep quality and melatonin in 12 adults who wore blue-light shield or control eyewear 2 hours before sleep while using a self-luminous portable device, and assessed visual quality for the two eyewear types. Overnight melatonin secretion was significantly higher after using the blue-light shield (P < 0.05) than with the control eyewear. Sleep efficacy and sleep latency were significantly superior for wearers of the blue-light shield (P < 0.05 for both), and this group reported greater sleepiness during portable device use compared to those using the control eyewear. Participants rated the blue-light shield as providing acceptable visual quality
Article fished in the ALAN Research Literature Database